*{
  box-sizing: border-box
}
body{
  margin: 0px;
}
.clear-fix:after{
  content: '';
  display: block;
  clear: both;
}
.tab-bar{
  position: fixed;
  bottom: 0;
  width: 100%;

}
.tab-item{
  width: 25%;
   height: 57px;
   border: 1px solid black;
   text-align: center;
   line-height: 57px;
   float: left;
}
#app {
  font-family: 'Avenir', Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-align: center;
  color: #2c3e50;
  margin-top: 60px;
}